Turtles survived dinosaur-killing extinction event

Meet the Boremys river turtle, a hardy fellow who shrugged
off the 65 million-year-old meteorite impact that did in the dinosaurs.

American paleontologists discovered fossilised remains of
Boremys, a turtle from the Baenid family, in North Dakota and
Montana. The specimen was uncovered in deposits from the Paleocene era, a
geologic epoch just after the extinction event.

Most groups of animals saw high rates of extinction at the
Cretaceous/Paleocene
boundary, but the turtles lived on. "This find further confirms
that turtles were not fazed by the meteorite that killed the
dinosaurs 65 million years-ago," said lead author Tyler Lyson from
Yale University.

In fact, if you just looked at turtle history during this time you wouldn't even notice that
one of the most catastrophic extinction events in the Earth's
history had just occurred. So far, fossil records show that at
least eight types of baenid turtles carried on.

How did they fare so well? Co-author Walter Joyce of the
University of Tubingen's Institute for Earth Sciences toldDiscovery News that the animal's hibernation
patterns -- where aquatic turtles dig and hide in mud holes when
its too cold or too dry -- could have also helped them weather the
meteorite impact.

The creature did eventually die out, though, and became
extinct around 42 million years ago. Joyce explains that baenids
could not retract their heads, like modern turtles, so would likely have been eaten to extinction
by small mammals.